Self-regulation is relevant to understanding the teaching–learning process; however, few studies have focused on teachers’ self-regulatory processes. The aim of this study was to characterize and analyze the relationship between teachers’ and students’ self-regulation. The design was cross-sectional and correlational. The sample consisted of 1481 participants (students n = 1123 and teachers n = 358) from 25 secondary schools in 17 cities of the Biobío region of Chile. In students, self-regulatory strategies were found to be deployed only half of the time; women were more self-regulated, and there was no difference in the levels of self-regulation according to grade. Teachers, it was found, almost always self-regulate their teaching, and the variables that influence their self-regulation are motivation, gender, and age, explaining between 25% and 28% of the variance. Positive and small correlations were evidenced between teacher role disposition with learning performance (rho = 0.10, p < 0.05) and teacher role self-evaluation with both learning performance and self-evaluation of learning in their students (rho = 0.12, p < 0.05). This study provides relevant evidence and proposes changes that could have a positive impact on teacher training and improve current teaching–learning practices in Chile, which would contribute to the quality of education.